The present invention relates to an image and audio recording apparatus.
One of the background arts in the technical field to which the present invention pertains is described in JP-A-2001-86456. JP-A-2001-86456 has as a problem the disclosure of “for setting a timer recording operation, in one day, the time when the recording is to be executed is separated from the time when the recording is not to be executed or though plural settings and recording intervals may be preset, the setting becomes the same in each day of the week. The timer recording operation did not have a facility of executing detailed settings and further had a difficulty in setting plural recording schedules in one day and making different settings in each day of the week.” JP-A-2001-86456 has as a solving means the disclosure of “For solving these problems, the present invention provides a capability of displaying two programs of a schedule-creating screen for one week on one screen so that plural programs may be easily set by switching the pages and of creating the recording preset screens (for specifying a recording interval, an image quality, an image resolution, a recording mode and so forth) in which various kinds of recording methods are preset so that the concerned preset may be specified in the concerned schedule.”
Another background art in the technical field to which the present invention pertains is described in JP-A-7-322202. The JP-A-7-322202 has as an object the disclosure of “An object is to enhance the using efficiency of a file device in the moving image storage apparatus” and as an arrangement the disclosure of “The non-video state detector 4 and the non-audio state detector 6 detect a non-video state and a non-audio state. For coding the moving image, in the non-video state, the non-video data code is used for coding and in the non-audio state the non-audio data code is used for coding. For synchronizing the video data with the audio data, the synchronous signal adder 7 adds the synchronous signal to the coded data. In decoding the moving image, based on the synchronous signal added in coding, the moving image is decoded by the synchronous detector 10, the image decoder 11 and the sound decoder 12.”
The image and audio recording apparatus provided with a harddisk drive mainly used for a monitoring system is required to record the image data and audio data as long as possible in a recording medium with a limited capacity. For the purpose of recording only a requisite minimum amount of data, therefore, the image and audio recording apparatus effectively uses various kinds of recording schemes such as high compression recording of data to be recorded, intermittent recording of data to be recorded, recording of data in response to detection of an alarm, recording of data in response to a motion detector and timer recording of data, for realizing long-term recording.
In the meantime, in a case that only minimum data is required to be recorded in the image and audio recording apparatus provided in the monitoring system, it is necessary to change data to be recorded depending on a monitoring time band and a monitoring object. For example, assume to monitor a shop in time bands: from 4:00 to 22:00 when one or more employees exist, the business hours from 10:00 to 20:00 and the lights-out time ranges from 22:00 to 4:00. During the business hours, the noises in the shop disallow the voices of the persons in the shop to be clearly captured. Hence, it is possible to stop recording of voices in the data recording. During the lights-out time, the shortage of light disallows the object to be captured by a monitoring camera. Hence, it is possible to stop recording of images in data recording. Further, during the time bands of 4:00 to 10:00 and 20:00 to 22:00 before and after the business hours, only the employees exist in the shop for the preparation of opening or closing the shop, it is necessary to clearly record the image as well as the conversation in care for illegal deeds, and it is necessary to record the image and the sound. Therefore, for recording minimum amount of data, it is necessary to specify recording of the image only in the business hours (10:00 to 20:00), recording of the sound only in the lights-out time (22:00 to 4:00), and recording of the image and the sound in the time except the business hours and the lights-out time (20:00 to 22:00, 4:00 to 10:00).
However, the prior art disclosed in the JP-A-2001-86456 does not make any consideration of separately setting recording of image and recording of sound when setting the timer recording. Hence, this prior art does not provide a capability of setting “recording of the sound only in a specific time band” or “recording of only the image in another specific time band”. Hence, in the case of setting the timer recording in the business hours (10:00 to 20:00), not only the necessary image but also the unnecessary sound are recorded. As such, disadvantageously, the unintentional recording of the unnecessary image or sound becomes an obstacle to long-term recording.
Further, the prior art disclosed in JP-A-7-322202 does not make any consideration of separately setting recording of image and recording of sound when setting a timer recording. Moreover, the data encoded from the picturelss image or the voiceless sound data still has a predetermined data amount.
Disadvantageously, therefore, the recording time is made shorter according to the predetermined data amount.